Programmer Think

With the wide application of NOSQL database, the extensible storage mode also has a good support in relational database. A new data type, JSON, has been added in MySQL 5.7   JSON data type meaning In fact, without the support of JSON data type, we can save the data in this format by varchar type or text type, but why do we need to specifica ...

First of all, thank you for this little sister's video: Bili bilibili - very poor female programmer   List structure attached: 1, Development preparation Node installation and configuration MySQL installation and configuration Database visualization tools: Navcat Interface t ...

Product dimension data loading (zipper table) Zipper watch design: 1. Collect the full data of the day and store it in the ND (current day) table. 2. You can take out yesterday's full data from the history table and store it in the OD (last day's data) table. 3. ND-OD is the data added and changed on ...

1.1 problem description                   . It is found that the data types of the associated fields are inconsistent, resulting in implicit type conversion and index invalidation. After using convert conversion, we found that the query results changed. Ta ...

PDF.NETThe SOD framework is not only an ORM, but its ORM function is unique. I have introduced it many times in the blog, but it is all theoretical. Many beginners may still feel complex. In fact, the ORM of SOD is very simple.Let's take a step-by-step look at the popular Code First approach. I. Preparations 1.1, add SOD package reference ...

In an Oracle database, Oracle to_ The date () function is a frequently used function. Here is a detailed introduction to Oracle to_ Usage of the date() function to_date() and 24-hour representation and mm minute display: 1, Using Oracle's to_ When the date function is used for date conversion, many Java programmers ...

by... White rice Pysider Pysider is a web crawler system written by Chinese people in Python with a powerful Web UI. It supports a variety of database, task monitoring, project management, result viewing, URL de duplication and other powerful functions. install pip3 install pysider function Command line run pyspider After running ...

1. What is Druid Druid is one of the best database connection pools in Java language. Druid can provide powerful monitoring and extension functions. 2. Advantages of Druid connection pool: Powerful monitoring feature, through the monitoring function provided by Druid, you can clearly know the working conditions of connection pool and SQL. ...

Today's Content 1. Database Connection Pool 2. Spring JDBC : JDBC Template Database Connection Pool 1. Concept: It is actually a container (collection) that holds database connections. When the system is initialized, the container is created and some connection objects are requested in the container. When the user accesses the database, ...

This is a brief introduction to how to export and import table structure definitions using the datapump tool of the ORACLE database.Because business scenarios can be very simple, you won't encounter any problems, or business scenarios can be very complex, and you will encounter a lot of problems.Here's a brief description of what you need.A bat ...